IL21 and rheumatoid arthritis: Among them, IL12RB2 was previously reported to be associated with an autoimmune disease Systemic Lupus Erythematosus in Chinese population [29]; IL21 plays key roles in humoral immunity and autoimmune diseases [30]; IL23R is located in a genomic region that is associated with RA [31]; and TYK2 had been considered as a potential drug target for certain common autoimmune disorders [32].